1. Field of the Invention
The present invention relates to the field of twin-piston food pumps. More particularly, the invention relates to a twin-piston food pump having a hydraulic cylinder coupled with each piston for driving the pistons and a linear transducer coupled with each cylinder for determining the positions thereof. Control circuitry coupled with the transducers determines the velocity of the cylinders and thereby the pistons and controls the application of hydraulic fluid through the cylinders to maintain a constant food product flow rate.
2. Description of the Prior Art
Twin-piston food pumps have proven themselves as valuable machines for pumping food products, especially viscous products such as ground meat. As the use of piston pumps becomes more common, it becomes more important for the pumps to deliver food products at a constant rate.
A constant flow rate is especially important for continuous operations such as a so-called "chub" machine or extrusion die process where it is important to maintain weight control or the shape of an extrusion. In the prior art, however, no provision has developed for maintaining the output from a twin-piston food pump with the desired level of precision.